Physics - Gravitation Question with Solution | TestHub

From mechanical energy conservation,

(Energy)_i= (Energy)_f

$-\frac{{\text{Gm}}^2}{\text{R}}=-\frac{{\text{Gm}}^2}{2\text{r}}+2\left[\frac{1}{2}{\text{mv}}^2\right]$

$\text{v}=\sqrt{-\text{Gm}\left[\frac{1}{\text{R}}-\frac{1}{2\text{r}}\right]}$